The present invention relates to a passenger airbag apparatus including a twin airbag having a left airbag section inflatable at a left side in a front area of an occupant and a right airbag section inflatable at a right side in the front area of the occupant. In particular, among the passenger airbag apparatus, the present invention relates to a passenger airbag apparatus including a deployment-limiting sheet that limits a deployment form of an airbag during inflation.
A passenger airbag apparatus includes a retainer arranged inside a dashboard, a folded airbag arranged in the retainer, an inflator configured to inflate the airbag, and a lid-configured to close the retainer.
Such an airbag may be a twin airbag including a base-end chamber coupled to the retainer, a left airbag section connected to the base-end chamber and being inflatable at a left side in a front area of an occupant toward a rear side of a vehicle body, and a right airbag section connected to the base-end chamber and being inflatable at a right side in the front area of the occupant toward the rear side of the vehicle body (for example, Japanese Unexamined Patent Application Publication No. 2004-244005).
In the passenger airbag apparatus including the twin airbag, when the inflator spouts gas, the gas is supplied from the inflator to the base-end chamber. As a result, the gas inflates the base-end chamber first. Then, the gas flows from the base-end chamber to the left and right airbag sections. As a result, the gas inflates the left and right airbag sections respectively at the left and right sides in the front area of the occupant toward the rear side of the vehicle body.
A prior publication (Japanese Patent No. 3406277) discloses a passenger airbag apparatus including a deployment-limiting sheet configured to limit a deployment form of an airbag during inflation.
In the patent, a strip-shaped deployment-limiting sheet having a predetermined length is provided between a folded airbag and an inner surface of a lid. One end of the deployment-limiting sheet is coupled to a rear edge of a retainer, and the deployment-limiting sheet covers the folded airbag.
When the airbag is inflated, the deployment-limiting sheet extends along a rear portion of the airbag during the inflation. Friction is produced between the deployment-limiting sheet and the rear portion of the airbag. Due to the friction, a front portion of the airbag is deployed first, and the rear portion of the airbag is subsequently deployed.
An object of the present invention is, in a passenger airbag apparatus including a twin airbag having left and right airbag sections, to decrease a protruding speed of the airbag toward a rear side of a vehicle body during inflation of the airbag.
Further objects and advantages of the invention will be apparent from the following description of the invention.